Feed aggregator

Author(s): A. V. Bernatskiy, I. I. Draganov, N. A. Dyatko, I. V. Kochetov, V. V. Lagunov, and V. N. Ochkin

Experimental and numerical studies of the features of the spatial distribution of plasma parameters in a discharge not limited by walls were performed. A discharge supported by a hollow cathode in helium at low pressure was ignited in a chamber with dimensions much larger than the dimensions of the …

[Phys. Rev. E 112, 025204] Published Thu Aug 14, 2025

Author(s): Michael F. Zhang, Seth Davidovits, and Nathaniel J. Fisch

We study the amplification of isotropic, incompressible turbulence through multiple planar, collisional shocks, using analytical linear theory. There are two limiting cases we explore. The first assumes shocks occur rapidly in time such that the turbulence does not evolve between shocks. Whereas the…

[Phys. Rev. E 112, 025205] Published Thu Aug 14, 2025

Author(s): Feiyu Li, Seth Dorfman, and Xiangrong Fu

The parametric decay instability (PDI) of Alfvén waves—where a pump Alfvén wave decays into a backward-propagating child Alfvén wave and a forward ion acoustic wave—is a fundamental nonlinear wave-wave interaction and holds significant implications for space and laboratory plasmas. However, to date …

[Phys. Rev. E 112, 025206] Published Thu Aug 14, 2025

Author(s): Shabbir A. Khan and Atsushi Fukuyama

Linear absorption of electromagnetic wave injected in a hot plasma is usually associated with non-normal incidence; here, it is shown that absorption can take place at normal incidence as well. By developing a kinetic model based on integral form of dielectric tensor in the presence of static electr…

[Phys. Rev. E 112, L023202] Published Thu Aug 07, 2025

Author(s): Iván Calvo, José Luis Velasco, Per Helander, and Félix I. Parra

Until now, quasi-isodynamic magnetic fields have been the only known stellarator configurations that, at low collisionality, give small radial neoclassical transport and zero bootstrap current for arbitrary plasma profiles, the latter facilitating control of the magnetic configuration. The recently …

[Phys. Rev. E 112, L023201] Published Wed Aug 06, 2025

Author(s): M. J. MacDonald, H. A. Scott, K. H. Ma, S. R. Klein, T. F. Baumann, R. W. Falcone, K. B. Fournier, C. M. Huntington, E. Johnsen, C. C. Kuranz, E. V. Marley, A. M. Saunders, M. P. Springstead, P. A. Sterne, M. R. Trantham, and T. Döppner

We present the use of x-ray fluorescence spectroscopy (XFS) to a sensitive temperature diagnostic in shocked foams at temperatures of 30–75 eV. Cobalt-doped foams were shock compressed using a planar drive at the OMEGA laser facility and photo-pumped with a Zn Heα x-ray source. Analysis of the resul…

[Phys. Rev. E 112, 025203] Published Tue Aug 05, 2025

Author(s): L. Ansia, P. Velarde, M. Fajardo, and G. O. Williams

Nonthermal photoionized plasmas are now established in the laboratory and require models that treat the atomic processes and electron distribution self-consistently. We investigate the effects of inelastic thermalization in iron under intense x-ray irradiation using the atomic model BigBarT, suited …

[Phys. Rev. E 112, 025201] Published Fri Aug 01, 2025

Author(s): H. P. Le, E. V. Marley, and H. A. Scott

Electron distributions in laser-produced plasmas will be driven toward a super-Gaussian distribution due to inverse bremsstrahlung absorption [Langdon, Phys. Rev. Lett. 44, 575 (1980)]. Both theoretical and experimental evidence suggest that fundamental plasma properties are altered by the super-Gau…

[Phys. Rev. E 112, 025202] Published Fri Aug 01, 2025

Author(s): Yu-Xi Liu, Jin-Yue Geng, Hai-Xing Wang, Hao Yan, Xu-Hui Liu, Su-Rong Sun, Ao-wei Liu, and Tao Wu

Achieving uniform, stable, and reliable erosion of electrode materials is crucial for enhancing the performance and lifespan of vacuum-arc devices. This study investigates the rotation and erosion characteristics of cathode spots on Cu and Ti cathodes with various applied magnetic fields. The result…

[Phys. Rev. E 112, 015213] Published Wed Jul 30, 2025

Author(s): S. Chintalwad and David J. Stark

We investigate the generation of kilotesla-level magnetic fields in laser-irradiated hollow conical targets through particle-in-cell simulations. This configuration proves effective in producing magnetic fields tens of kiloteslas in strength that persist on a picosecond timescale. Moreover, the holl…

[Phys. Rev. E 112, 015212] Published Mon Jul 28, 2025

Author(s): Michal Hnatič, Tomáš Lučivjanský, Lukáš Mižišin, Yurii Molotkov, and Andrei Ovsiannikov

We present a two-loop field-theoretic analysis of incompressible helical magnetohydrodynamics (MHD) in fully developed stationary turbulence. A key feature of helical MHD is the appearance of an infrared-unstable “masslike” term in the loop diagrams of the magnetic response function. Physically, thi…

[Phys. Rev. E 112, 015211] Published Thu Jul 24, 2025

Author(s): Zijin Zhang, Anton V. Artemyev, and Vassilis Angelopoulos

The transport of energetic particles in the heliosphere is profoundly influenced by interactions with coherent structures in the turbulent magnetic field of the solar wind, particularly current sheets. While prior studies have largely relied on idealized turbulence models, this work quantifies the r…

[Phys. Rev. E 112, 015209] Published Wed Jul 23, 2025

Author(s): Ilnaz I. Fairushin and Anatolii V. Mokshin

In this paper, the theoretical model of weak decaying collective excitations characteristic of many-particle systems with long-range interaction potentials is developed using the example of one-component strongly coupled Yukawa plasmas. The proposed model is based on the self-consistent relaxation t…

[Phys. Rev. E 112, 015210] Published Wed Jul 23, 2025

Author(s): Masaru Nakanotani, Luis Lazcano Torres, Gary P. Zank, and Edward Thomas, Jr.

The Jeans instability in a magnetized dusty plasma is considered a fundamental process in space, where magnetic fields are common. We investigate the Jeans instability in a magnetized dusty plasma using 1D and 2D particle-in-cell simulations, in which dust grains are treated as particles and the Poi…

[Phys. Rev. E 112, 015208] Published Mon Jul 21, 2025

Author(s): T. A. Shelkovenko, I. N. Tilikin, A. R. Mingaleev, V. M. Romanova, and S. A. Pikuz

The small-sized, low-voltage, and low-inductive KING generator (190–230 kA, 40 kV, 200–240 ns) was specially designed to work with X-pinches; however, it was unstable in its original design. In the present work, it is experimentally shown that an increase in the inductance of the output node of the …

[Phys. Rev. E 112, 015207] Published Thu Jul 17, 2025

Abstract

To meet the high-precision and high-integrity positioning demands of safety–critical applications, monitoring the quality of precise satellite products in global navigation satellite system (GNSS) precise point positioning (PPP) is crucial. This work employs ionosphere-free (IF) PPP with ambiguity resolution (PPP-AR) phase residuals to construct test statistics for monitoring the quality of precise satellite corrections. By utilizing precise satellite orbit and clock products from CODE, WUM, and GRG, the PPP-AR phase residuals were first analyzed with sample moments, Allan variance and power spectral density (PSD). The key findings are as follows: (1) The skewness and kurtosis results indicate that ambiguity-fixed phase residuals deviate from an ideal zero-mean Gaussian distribution and exhibit a super-Gaussian distribution. (2) Allan variance and PSD analysis reveal that flicker noise dominates the phase residuals. (3) The noise amplitudes are similar for all satellites, but certain differences are observed among different GNSS systems and satellite types. (4) The noise level of phase residuals is influenced by the receiver types, antenna types, and precise products from different analysis centers. Leveraging the error characteristics, the two-step Gaussian overbounding (OB) method was employed to estimate the corresponding OB parameters of the phase residuals. The overbounding results demonstrate that, under similar conditions, phase residuals can be bounded by the calculated bound within the acceptable integrity risk after removing the detected outliers. Anomaly monitoring experiments further show that phase residuals can effectively capture anomalies in precise satellite corrections, with the set threshold successfully detecting such anomalies.

The measurement of virtual height of the sporadic E layer (h'Es) is very sensitive to the type of ionosonde used and the calibration processes. The ionosondes used by the national institute of communication an...

Abstract

Solar photospheric abundances and CI-chondrite compositions are reviewed and updated to obtain representative solar system abundances of the elements and their isotopes. The new photospheric abundances obtained here lead to higher solar metallicity. Full 3D NLTE photospheric analyses are only available for 11 elements. A quality index for analyses is introduced. For several elements, uncertainties remain large. Protosolar mass fractions are H (X = 0.7060), He (Y = 0.2753), and for metals Li to U (Z = 0.0187). The protosolar (C+N)/H agrees within 13% with the ratio for the solar core from the Borexino experiment. Elemental abundances in CI-chondrites were screened by analytical methods, sample sizes, and evaluated using concentration frequency distributions. Aqueously mobile elements (e.g., alkalis, alkaline earths, etc.) often deviate from normal distributions indicating mobilization and/or sequestration into carbonates, phosphates, and sulfates. Revised CI-chondrite abundances of non-volatile elements are similar to earlier estimates. The moderately volatile elements F and Sb are higher than before, as are C, Br and I, whereas the CI-abundances of Hg and N are now significantly lower. The solar system nuclide distribution curves of s-process elements agree within 4% with s-process predictions of Galactic chemical evolution models. P-process nuclide distributions are assessed. No obvious correlation of CI-chondritic to solar elemental abundance ratios with condensation temperatures is observed, nor is there one for ratios of CI-chondrites/solar wind abundances.

The January 2022 Tonga volcanic eruption generated atmospheric pressure waves that propagated over the ocean’s surface and triggered a meteotsunami. This meteotsunami caused significant amplitudes exceeding 10...

Abstract

Accurately modeling and prediction the nonlinear motion of GNSS (Global Navigation Satellite System) coordinate time series holds significant theoretical and practical value for the study of geodynamics. A novel integrated network, named Ensemble Learning method based on Signal Source Driver (ELSSD), is proposed, which leverages the strengths of Long Short-Term Memory (LSTM) and Deep Self-Attention Neural Network (DSANN), while integrating GNSS loading data as an additional data source. Additionally, a multi-track synchronous sliding window data processing strategy is designed to address the challenge of multi-source data fusion input. The effectiveness of this algorithm is validated using GNSS coordinate time series from 186 global stations over a period of 10 years. Experimental results initially illustrate that, when accounting for displacement caused by environmental loading effects, there is a marked improvement in the modeling and prediction accuracy compared with GNSS input-only. Furthermore, the application of three ensemble network strategies-Bagging, Boosting, and Stacking-have further been demonstrated to enhance modeling and prediction accuracy. Compared with LSTM and DSANN networks, the proposed ELSSD algorithm achieves an average RMSE (Root Mean Square Error) of 3.6 mm for both modeling and prediction, with modeling accuracy improvements of 4.8% and 6.2%, while prediction accuracy improvements of 5.4% and 5.9%, respectively. With respect to the traditional Least Square method, there is an improvement of 22.1% and 27.9% in modeling and prediction accuracy, respectively. Regarding noise characteristics, there is a significant reduction in colored noise amplitude, with decreases of 36.7% and 36.0% observed in modeling and prediction, respectively. Simultaneously, the velocity uncertainty experiences an average reduction of 27.1% and 27.5%. The average velocity differences are measured at 0.06 mm/year and 0.24 mm/year, respectively. Hence, our findings suggest that the ELSSD algorithm emerges as an effective methodology for handling multi-source data input in GNSS coordinate time series, presenting promising practical applications in the field.